Now, if I navigate to the, what I believe is the network manager gui found in under Debian Stretch settings, simply turn off and back on the wired connection via the toggle, I will then get the gateway and I can access the Internet as expected.

I have also tested this with WiFi; however after a reboot, I will get the correct GW and can route past my LAN.

Configuration:I have a static IP configured: This was performed with the network manager GUI IP, Mask and GW.... DNS is hard set

Some back story:I have built a new PC, new MoBo and CPU, etc.... Same HDD as on the previous built and had no issues prior with same static configuration. I did need to 'perform some magic google searching' to get the new video card (GEFORE GT1030) and the Intel drivers for WiFi. The NIC worked out the box (but had same GW issue) but no WiFi until I loaded the drivers.

Sorry that this make it a bit of a mess, but I hope to learn quite a bit more with this issue. Preferably, I wish to continue to use the 'stock' network manager GUI and I really appreciate your time. Please request from me additional details that may need to help solve the issues, as well as teach me a lesson or two. As I like to say, you don't know, what you don't know

Thank you and best regards,

########################## Fixed the issue ##########################

Follow up:

I did manage to get this to work, but I am still a bit perplexed why it needed to be manually configured versus using the network manager. I edited /etc/network/interface and had to add in the routes are well for it to work as expected

Not sure if this was the best way to correct it or not, but wanted to add in these note in the event that there is a way to get this to work with network manager to if someone else is having this issue